Using AUTO for Stability Problems

This website provides information about the mini-course "Using AUTO for Stability Problems" (David Lloyd and Bjorn Sandstede). This mini-course is part of the workshop The stability of coherent structures and patterns that will be held 11-12 June 2012 at the University of Washington in Seattle/Washington.

Overview

The mini-course "Using AUTO for Stability Problems" will provide an introduction to using Auto07p for setting up and solving algebraic and nonlinear boundary-value problems related to pattern formation. Specifically, we will learn how to compute symmetric and asymmetric localized roll structures in the Swift-Hohenberg equation and fronts in the Nagumo equation. In addition, we plan to discuss how the stability of these structures can be assessed in Auto07p or in Matlab. If time permits, we will also explore how wave-train solutions and their essential spectra can be computed using Auto07p. Much of the mini-course will be spent on hands-on examples. Thus, bringing a laptop with Auto07p installed is the best way of benefitting from this mini-course:

Essential: Laptop with Auto07p installed (see below for the specific requirements and for installation instructions).

Optional: Matlab installed.

The patterns shown to the left are (from top to bottom): 1D localized rolls, planar hexagon pulses, time-periodic planar oscillons, and planar stripe patterns; all of them were computed in Auto07p.

Installation of Auto07p

Downloading Auto07p:

There is no need for installing PLAUT, PLAUT04, or GUI94 (in fact, the installation of PLAUT04 can be quite complicated), but a Fortran95 compiler Python need to be installed. After you installed Auto07p, please run one of the demos: instructions can be found at the end of the installation guide for Macs. You can also download a sample ".profile" file that sets your path: change the name of the file to ".profile" and move it to your home directory; you may have to adapt your file depending on where you installed AUTO.

Installation under Linux:

Please see pages 12-13 of the Auto07p manual. In Ubuntu, you can use the Synaptic Download Manager (found under "System -> Administration -> Synaptic Package Manager") to install gfortran and python.

Installation under Mac OS X:

Please see pages 13-14 of the Auto07p manual. Alternatively, follow the more detailed instruction linked to below:

Installation under Windows:

Please see pages 14-15 of the Auto07p manual. It is essential to have a text editor available that can access Auto07p files. Alternatively, it might be easier to install Ubuntu under Windows using Wubi and then follow the instructions for Linux above. Wubi allows you to run Ubuntu alongside Windows and delete it from your system within Windows.

Support:

If you need help with the installation of Auto07p, please first search the internet and online forums and look for solutions there. If nothing works, please contact Bjorn Sandstede and include the following information: your operating system, a detailed list of the commands you tried and the error messages you received, and the version of fortran and python you installed. Please be aware though that we cannot provide extensive technical support given the size of the workshop.

Frequently asked Questions

Installing the developer's tools Xcode under Mac OS 10.6 or earlier: these are not available from the App Store; instead follow the instructions below:

Check at Wikipedia which version of Xcode you need for your operating system.

Register as a developer and download Xcode afterwards (you can search for the correct Xcode version at Apple's website). Registration is free, and you can use your iTunes account for this purpose.

The command-line tools are installed automatically with older versions of Xcode.

Python under Mac OS X: It is also possible to download EPD Free, which includes the packages Numpy and Matplotlib.

"Incompatible architecture" errors under Mac OS X Lion: if you get errors about incompatible architectures after or during installation of AUTO under Mac OS X Lion, please open a terminal, go to the directory "auto/07p/", and type "make superclean" followed by "./configure CFLAGS=-m32 FCFLAGS=-m32" and "make" (all at without the quotes).

Virus alert during installation on Windows: if you have anti-virus software installed under Windows, the "./configure" program may stop prematurely and your anti-virus software may indicate that it found a virus. In this case, disable your anti-virus program, run "./configure", and then enable the anti-virus program again. The reason for the warning is that "./configure" checks whether executable programs can run on your computer: it creates a test file, compiles it, and then runs it, which causes the anti-virus program to interrupt the "./configure" program.